Towards Informed Swarm Verification

Abstract

Abstract. In this paper, we propose a new method to perform large scale grid model checking. A manager distributes the workload over many embarrassingly parallel jobs. Only little communication is needed between a worker and the manager, and only once the worker is ready for more work. The novelty here is that the individual jobs together form a so-called cumulatively exhaustive set, meaning that even though each job explores only a part of the state space, together, the tasks explore all states reachable from the initial state.

Recent advances in interactive and automated analysis

“…The spectrum of properties considered ranges from invariants, as in the parallel variant of the Murphi model checker [36], up to LTL properties as handled by the parallel variants of SPIN [24,23]. A recent parallelization approach for verifying LTL properties in the explicitstate setting is the so-called swarm verification, in which a large number of parallel processes cooperate in exploring the state space and detecting accepting cycles [40] or strongly connected components [35].…”

System Level Formal Verification via Distributed Multi-core Hardware in the Loop Simulation

“…Note that we propose an embarrassingly parallel algorithm for (black box) formal verification of hybrid systems. Embarrassingly parallel verification algorithms have also been investigated in [22], as for finite state system verification, and in [23], as for symbolic testing of programs. Such approaches are close in spirit to ours, although they differ from ours as for the class of systems considered (we focus on hybrid systems whereas the above papers focus on discrete systems) as well as for the modelling approach (our black box algorithm rests on the disturbance model whereas the above papers both present white box algorithms resting on the system model).…”

The HIVE Tool for Informed Swarm State Space Exploration

“…C( , ) = states that if actions and can be performed by different processes, then the result is action in the system. For the formal details, see [14]. We assume that the A i are disjoint (if this is not the case, then some rewriting can resolve this) 2 and that no action is involved in more than one rule defined by C (either as an input, or as a result).…”

“…However, if a property holds, each worker will exhaustively explore the whole reachable state space, which means that the benefits of parallelisation are completely lost. Recently, we proposed a mechanism to bound each worker to a particular reachable strict subset of the set of reachable states, in such a way that together, the workers explore the whole state space [14]. This mechanism is compatible with any action-based formalism such as µCRL [8], where each transition in a state space is labelled with some action name corresponding with system behaviour.…”

“…This mechanism is compatible with any action-based formalism such as µCRL [8], where each transition in a state space is labelled with some action name corresponding with system behaviour. In this paper, we explain how the Heuristics Instructor for parallel VErification (HIVE) tool, which resulted from [14], works in practice. Section 2 presents the functionality of the HIVE tool together with some new algorithms implemented in the LTSMIN tool suite [4].…”